Over the past decade, stenting of lateral sinus stenosis has been used to treat idiopathic intracranial hypertension. Two types of stenoses have been identified: extrinsic and intrinsic.The aim of this study was to report the results of our use of this procedure to treat patients with extrinsic or intrinsic stenoses in idiopathic intracranial hypertension.We retrospectively studied clinical, radiological, and manometric data from patients with idiopathic intracranial hypertension who were treated at our institution between January 2009 and January 2015 by stenting of the lateral sinus.Data were studied from 19 women and 2 men. Average body mass index was 29 kg/m 2 , and the median age at stenting was 33 years. Patients with extrinsic stenoses were younger than those with intrinsic stenoses. Transstenotic gradients measured with patients under general anesthesia were lower than those measured with patients under local anesthesia. In all cases, stenting was effective for papilledema and pulsatile tinnitus. Seventeen patients reporting headaches found that they disappeared completely after stenting. Two complications without long-term effects were reported.Irrespective of the type of stenosis, stenting of lateral sinus stenoses is an effective treatment for intracranial hypertension symptoms. At our institution, this treatment has replaced draining of cerebrospinal fluid when treatment with acetazolamide has proved to be ineffective.
Pending the results of randomized controlled trials (RCT) evaluating endovascular treatment (EVT) for distal occlusions, we aimed to investigate the safety and efficacy profiles of EVT for distal-M2 strokes in clinical practice.We report data from the multicentric prospective registry ETIS (Endovascular Treatment for Ischemic Stroke) (ClinicalTrials.govIdentifier: NCT03776877) including 21 stroke centers in France.Our study received approval from our Intstitutionl Review Board (ID RCB 2017-A03457-46).Oral informed consent from the patient and/or a trustworthy person was collected by local investigators.We included patients with the following criteria: age ≥18 years; acute ischemic stroke (AIS) due to primary distal-M2 occlusion; and time from symptom onset to puncture ≤6 hours.An M2 occlusion was considered distal if it was above the horizontal line delineating the mid-height of the insula.The primary outcome was a favorable outcome, defined as a modified Rankin Scale (mRS) ≤2 at 90 days.Secondary outcomes included excellent outcome (mRS ≤1 at 90 days); 90-day all-cause mortality; early neurological improvement defined as a National Institutes of Health Stroke Scale (NIHSS) ≤1 or an improvement of ≥8 points compared with baseline at 24 hours post-EVT; procedure-related complications, including embolus to a new territory, perforation, and dissection; parenchymal hematoma (PH); symptomatic intracranial hemorrhage (sICH) defined as a hemorrhage on the follow-up computed tomography/magnetic resonance imaging scan and an increase of 4 points in the NIHSS score, according to the European Collaborative Acute Stroke Study classifications; 1 successful reperfusion defined as an improvement of at least 1 point in the modified Thrombolysis In Cerebral Infarction (mTICI) score between the first and the last angiogram (2a to 2b-2c-3, 2b to 2c-3).An additional systematic review with meta-analysis has been performed on distal-M2 thrombectomy and is detailed in Supplementary Material.To identify outcome predictors in the present series, multiple regression models were fitted using the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). 2 Missing data were excluded.All analyses were completed using Stata 17 (StataCorp, College Station, TX, USA), RStudio version 1.4.1106(https://posit.co/),and the R General Package for Meta-Analysis (version 6.0-0; R Foundation for Statistical Computing, Vienna, Austria).During the study period, 157 patients underwent EVT for an AIS due to a distal-M2 occlusion.Demographic and procedural data are shown in Table 1.Median NIHSS at baseline was 12
Background: During the last decade, our understanding of cerebrospinal fluid (CSF) physiology has dramatically improved, thanks to the discoveries of both the glymphatic system and lymphatic vessels lining the dura mater in human brains. Evidence Acquisition: We detail the recent basic science findings in the field of CSF physiology and connect them with our current understanding of the pathophysiology of idiopathic intracranial hypertension (IIH). Results: Transverse sinus (TS) stenoses seem to play a major causative role in the symptoms of IIH, as a result of a decrease in the pressure gradient between the venous system and the subarachnoid space. However, the intracranial pressure can be highly variable among different patients, depending on the efficiency of the lymphatic system to resorb the CSF and on the severity of TS stenoses. It is likely that there is a subclinical form of IIH and that IIH without papilledema is probably under-diagnosed among patients with chronic migraines or isolated tinnitus. Conclusions: IIH can be summarized in the following pathological triad: restriction of the venous CSF outflow pathway—overflow of the lymphatic CSF outflow pathway—congestion of the glymphatic system. To better encompass all the stages of IIH, it is likely that the Dandy criteria need to be updated and that perhaps renaming IIH should be considered.
Abstract The vascular system regulates brain clearance through arterial blood flow and lymphatic drainage of cerebrospinal fluid (CSF). Idiopathic intracranial hypertension (IIH), characterized by elevated intracranial pressure and dural venous sinus stenoses, can be treated by restoring venous blood flow via venous stenting, suggesting a role for venous blood flow in brain fluid clearance. Using magnetic resonance imaging (MRI) in IIH patients and healthy controls, we identified that dural venous stenoses in IIH were associated with impaired lymphatic drainage, perivenous fluid retention, and brain fluid accumulation. To investigate this further, we developed a mouse model with bilateral jugular vein ligation (JVL), which recapitulated key human findings, including intracranial hypertension, calvarial lymphatic regression, and brain swelling due to impaired clearance. To further dissect the respective roles of meningeal lymphatic vessels and venous blood flow in brain clearance, we performed JVL in mice with lymphatic depletion. These mice exhibited spontaneous elevated intracranial pressure, but JVL did not further exacerbate this effect. Moreover, the synchronous restoration of brain clearance and meningeal lymphatics observed in mice after JVL was absent in lymphatic-deficient mice.Transcriptomic analyses revealed that lymphatic remodeling induced by JVL was driven by VEGF-C signaling between dural mesenchymal and lymphatic endothelial cells. These findings establish the dural venous sinuses as a critical platform where venous blood flow interacts with mesenchymal cells to preserve meningeal lymphatic integrity and function, essential for brain fluid clearance.
Spinal arteriovenous fistulas (SAVFs) are challenging lesions to treat by endovascular means. Our purpose was to report our early experience with dual lumen balloons (DLBs) for embolization of SAVFs using ethylene vinyl alcohol (EVOH) (the so-called 'balloon pressure technique' (BPT)).During the inclusion period, 10 consecutive patients (nine men, mean age 61.6 years) underwent endovascular treatment of a SAVF (seven dural SAVFs and three epidural SAVFs) at a single institution using the BPT. DLBs were used in all cases. In seven cases (70%), a regular DLB was used, while in three cases (30%), low profile DLBs were used. EVOH was used as the liquid embolic agent in all cases. Technical and clinical complications were systematically recorded. Clinical and angiographic outcomes were systematically evaluated more than 3 months after the procedure.Complete cure of the SAVF by endovascular means alone was obtained in 80% of cases (8/10). For the two patients with incomplete SAVF occlusion, surgery was successfully performed secondarily. No recurrence was found at the 3 month follow-up in the eight patients for whom complete occlusion was obtained at the end of the embolization procedure. No permanent clinical complication was recorded using the BPT. Clinical improvement was observed in 6/10 (60%) cases.BPT was a feasible technique, with regular or low profile DLBs, for embolization of SAVFs. Our preliminary results suggest the safety and effectiveness of this technique.
Based on their clinical and radiological patterns, idiopathic CSF rhinorrhea and idiopathic intracranial hypertension can represent different clinical expressions of the same underlying pathological process. Transverse sinus stenoses are associated with both diseases, resulting in eventual restriction of the venous CSF outflow pathway. While venous sinus stenting has emerged as a promising treatment for idiopathic intracranial hypertension, its efficiency on idiopathic CSF leaks has not been very well addressed in the literature so far. The purpose of this study was to report the results of transverse sinus stenting in patients with spontaneous CSF rhinorrhea associated with transverse sinus stenoses.From a prospectively collected database, the authors retrospectively collected the clinical and radiological features of the patients with spontaneous CSF leakage who were treated with venous sinus stenting.Five female patients were included in this study. Transverse sinus stenoses were present in all patients, and other radiological signs of idiopathic intracranial hypertension were present in 4 patients. The median transstenotic pressure gradient was 6.5 mm Hg (range 3-9 mm Hg). Venous stenting resulted in the disappearance of the leak in 4 patients with no recurrence and no subsequent meningitis during the follow-up (median 12 months, range 6-63 months).According to the authors' results, venous sinus stenting may result in the disappearance of the leak in many cases of idiopathic CSF rhinorrhea. Larger comparative studies are needed to assess the efficiency and safety of venous stenting as a first-line approach in patients with spontaneous CSF rhinorrhea associated with transverse sinus stenoses.
Meningeal lymphatic vessels (MLVs) were identified in the dorsal and caudobasal regions of the dura mater, where they ensure waste product elimination and immune surveillance of brain tissues. Whether MLVs exist in the anterior part of the murine and human skull and how they connect with the glymphatic system and extracranial lymphatics remained unclear. Here, we used light-sheet fluorescence microscopy (LSFM) imaging of mouse whole-head preparations after OVA-A555 tracer injection into the cerebrospinal fluid (CSF) and performed real-time vessel-wall (VW) magnetic resonance imaging (VW-MRI) after systemic injection of gadobutrol in patients with neurological pathologies. We observed a conserved three-dimensional anatomy of MLVs in mice and humans that aligned with dural venous sinuses but not with nasal CSF outflow, and we discovered an extended anterior MLV network around the cavernous sinus, with exit routes through the foramina of emissary veins. VW-MRI may provide a diagnostic tool for patients with CSF drainage defects and neurological diseases.
